1. Field of the Invention
The invention relates to a printed circuit card carrying in particular components boxes positioned and fixed by welding, as well as dissipation means of the heat emitted by the boxes.
Such a card comprises:
a mounting face for the boxes, PA1 a welding face of the boxes, PA1 conductive tracks provided on the mounting face and on the welding face, PA1 holes connecting tracks of the one and the other face, the boxes being provided with connecting clips inserted in the holes, and PA1 a thermal dissipator which is mounted on the card for dissipating the heat emitted by the components boxes.
2. Description of the Prior Art
In order to avoid the problems related to the compensation of backlashes encountered with the dissipators usually mounted directly on the boxes a thermal linking path is provided for connecting the boxes to the dissipator. It is observed in practice that the electronic components presently available on the market, which are positioned on a printed card withstand temperatures higher than the card. It is thus essential to improve the calorific exhaust efficiency permitted by the dissipator and by the thermal path connecting the boxes to this dissipator, if the temperature of the card must be kept lower than a given value, e.g. typically around 105.degree. C.
It is known, according to the French patent No. 2560731 to provide between a component box and the card which carries it, a copper plate constituting a thermal shunt which can extend up to the dissipator. A conduction thermal link is set up between the plate and the box by means of a plastic ceramic strip. The construction of such a cooling system is obviously intricate.